SACD..with its DSD digital protocol is definetely better than redbook. I can easily hear that on my modest system.
*however*
w/the right DAC, redbook is not dissapointing.
i've only heard one high end vinyl setup, and it was like liquid music pouring over me.
I have yet to get that experience w/any digital front end...but then again i've never heard really high-end digi..something like an EMMLabs DAC6 and SACD transport...
or the Sony 9000ES SACD and matching reciever that takes pure DSD over i.Link format.
I'm convinced that DSD is a better sounding format than PCM.
From what i've heard from people who have had the exposure (and whos ears I trust) is that anything Ed Meitner gets inside of tends to sound very good... and that until you've heard something like the EMM labs equipment, then you have not fully heard digitals potential.
There are plenty of great DACs out there, but one that upsamples to DSD designed by a guy who has been so involved on that protocol for so long...that says something (to me). And from what I understand that is what the DAC 6 does.
fwiw, that is also what the sony STR-DA2,3,5,9000ES digital recievers do if you feed them a PCM signal.
Any way....this peaks my interest to stay with digital for the long haul as I *know* that the technology to unlock those bits will just continue to improve and get cheaper, where as vinyl doesn't seem to sway in that direction, me thinks.